would you tell us that story? give us an outline of the spillover and spread? >> there's an interesting segue there, into talking about bats it one of the world's experts on that viruses, over the, -- charlie, just raise your hand. so, charlie is a virologist who for many years was engaged in a lot of diagnostics primarily antibody diagnostics at the centers for disease control in fort collins, colorado. and he wrote a paper a few years ago which talked about bats and the fact that the bats are reservoirs for a large number of different pathogens. we have people and injure a and sars, and many others species let me just parenthetically ask, would you describe what a reservoir or a reservoir host is? what host that place kick was classically when we think of a reservoir it's an animal that is capable of being infected, carrying the infection for long period of time. and literally serving as a reservoir for infection of the species to quickly what happens is there's an end host like humans where it doesn't, the virus doesn't replicate particularly well. so it doe